Every London tube station will have 4G and 5G by the end of 2026
Key Points
- TfL has promised full 4G and 5G coverage across all 121 underground Tube stations and tunnels by the end of 2026
- Coverage stood at about 60% of stations in June, with the original 2024 deadline pushed back to add 5G capability
- Boldyn Networks is funding the £1 billion-plus build under a 20-year concession at no cost to the taxpayer
- Nine base station hotels connect BT, Virgin Media O2 and VodafoneThree to the underground network
- Ookla found Tube signal already stronger than street level where deployed, with almost 20% of connections on 5G
Transport for London has committed to full 4G and 5G coverage across all 121 of the Tube’s underground stations and its tunnels by the end of 2026, up from about 60% of stations in June.
The Financial Times reported the update on the rollout on Wednesday (2 September), including new detail on how the network operates and why it ran two years late.
TfL first planned to finish 4G coverage in 2024 and then moved the deadline to the end of 2026, partly so the network could carry 5G from day one and support an upgrade to 6G later.
Boldyn Networks, a London-based infrastructure group majority owned by Canadian pension fund CPP Investments, is building the network under a 20-year concession it won in June 2021. Work started in earnest at the beginning of 2022, with around 700 staff installing equipment at about 20 locations each night.
Boldyn can only work between midnight and 5am because trains run for the rest of the day, and the narrow Victorian-era tunnels leave far less room for equipment than newer systems such as New York’s.
“You’re talking about one of the most complex tube networks in the world,” said Brendan O’Reilly, chief executive for the UK and Ireland at Boldyn Networks.
Deep stations serving several lines, such as Finsbury Park, ranked among the hardest to fit, and engineers also had to maintain an independent power supply for the emergency services network.
The total investment will exceed £1 billion by completion, covering hundreds of kilometres of fibre, thousands of antennas and nine “base station hotels” where Boldyn’s network connects to BT, Virgin Media O2 and VodafoneThree.
Not good enough
The development comes as a top executive at the UK’s largest mobile operator has said its own network quality is not good enough for the AI era.
Andrea Donà, Networks Director at VodafoneThree, told the Guardian that the country’s mobile networks are already falling short of what today’s services demand.
“I am embarrassed today at the level of quality of our network[s],” said Donà, networks director at VodafoneThree.
He argued that the UK deserves better than what EE, O2 and VodafoneThree currently deliver, and that reform is needed to close the gap.
The numbers behind that assessment are unflattering. A recent report from consumer group Which?, based on Opensignal data, found UK mobile coverage trailing all 27 EU member states and every other G7 nation.
That analysis placed the UK 57th globally for network performance, 70th for download speeds and 55th for the reliable quality needed for video calls, streaming and gaming.
Much of the AI infrastructure debate has focused on datacentres and the water and energy they need to train and run models. The networks that carry the resulting traffic have attracted far less attention.
Broadband is the part of the picture that has improved, as BT’s Openreach and rival providers roll full-fibre connections across the country. Mobile upgrades have not kept pace with that progress.
Donà compared the coming strain to the signal loss consumers already experience at large public events, such as a concert at Wembley or the British Grand Prix at Silverstone.
He said that the crowd-related congestion people encounter today is an early indication of what constant AI usage will demand from mobile capacity.
